4.	a. High-Low: Y = $8,700 + $750X ($34,200 - $20,700)/(34 – 16) = $750 per event; $750 × 34 = $25,500; $34,200 - $25,500 = $8,700 b. TC = FC + VCu(volume) TC = $8,700 + $750 x 25 TC = $27,450